Tool adjustment device



June 2, 1970 P. D. BAUKNIGHT ET AL 3,514,990

TOOL ADJUSTMENT DEVICE 2 Sheets-Sheet 1 Filed Dec. 18. 1967 PRIOR ARTFI.l

-FIG.2

INVENTORS PAUL D. BAUKNIGHT ROBERT LAHRHEIM ATTORNEY June 2, 1910 P, D,BAUKNIGHT E'l AL 3,514,990

TOOL ADJUSTMENT DEVICE Filed Dec. 18, 196'? z Sheets-Sheet 2 l GD "h "1S r Ii h 36 80 I0 INVENTORSI 7 PAUL D. BAUKNIGHT n ROBERT LAHRHEIMwikqdwwl ATTORNEY United States Patent 3,514,990 TOOL ADJUSTMENT DEVICEPaul D. Bauknight, Cranford, and Robert Lahrheim, Colonia, N..I.,assignors to The Thomas & Betts Co., Elizabeth, N.J., a corporation ofNew Jersey Filed Dec. 18, 1967, Ser. No. 691,442

Int. Cl. 821d 7/06 US. Cl. 72-410 6 Claims ABSTRACT OF THE DISCLOSUREThis disclosure is directed to a tool adjustment device and moreparticularly an adjustment device for operation 'with the full-strokecompelling mechanism. The disclosure provides an adjustment device tocompensate for the build-up and varying tolerances of hand tools havingfullstroke compelling mechanisms. In order to insure that thefull-stroke compelling mechanism will release at the proper point in thecompression cycle the disclosure provides an adjustable pawl cooperatingwith the rachet of the full-stroke compelling mechanism. The pawl ismounted upon an eccentric pawl pin which may be rotated in order toposition the pawl adjacent the desired land, or tooth, of thefull-stroke compelling mechanism ratchet. Locking means are provided tolock the pawl to the eccentric pawl pin to prevent relative motiontherebetween. The eccentric portion of the eccentric pawl pin isprovided with range of eccentricity between the best and worst caseconditions so that the tool may be continually readjusted to compensatefor variances in the size of the crimping dies and tolerance variationsoccurring during manufacture and dimensional changes due to wear of thevarious operative portions of the crimping tool.

BACKGROUND OF THE INVENTION Field of the invention The invention isdirected to the field of tools having full-stroke compelling mechanismsto permit their continuous readjustment to compensate for variations inthe tool operation caused by manufacture and wear. Although, in thespecific embodiment to follow, the tool adjustment device is directed toa hand tool of the toggle type having a full-stroke compelling mechanismit is similarly applicable to electrically, pneumatically, hydraulicallyand other tools operated by similar means which similarly havefull-stroke compelling mechanisms.

Description of the prior art Prior art hand tool of the toggle type arerepresented by devices of the type shown in US Pat. 2,696,747, issuedDec. 14, 1954, to Martin D. Bergan for a Toggle- Actuated Crimping ToolWith Full-Stroke Compelling Mechanism, owned by the assignee of theinstant invention. This device employs a fixed pawl which is preset atthe factory at the time of tool assembly and cannot be adjusted in thefield. This was done partially to prevent the insertion into the tool ofdies or other devices for which the tool was not designed to handle andwhich otherwise might impair its operation. Errors in the registrationof the pawl with respect to the ratchet of the full-stroke compellingmechanism can only be handled by sending the tool back to themanufacturer and having the pawl removed therefrom and replaced byanother pawl or having the pawl ground down to properly meet the desiredpoint of the rachet of the full-stroke compelling mechanism. Suchprocedures are time consuming and expensive, requiring that the tool bereturned to the manufacturer during which time it is lost to the user.

3,514,990 Patented June 2, 1970 SUMMARY OF THE INVENTION The presentinvention overcomes the difiiculties noted above with respect to theprior art devices by providing a pawl arrangement which is adjustableand can be reset in the field at any time in order that the pawlproperly mate with the rachet of the full-stroke compelling mechanism.This is achieved by replacing the fixed pawl pin, found in the prior artdevice noted above, with an eccentric pawl pin and mounting thereon apawl having a locking mechanism such that the pawl may be positionedupon the eccentric pawl pin and the eccentric pawl pin rotated in orderto bring the tip of the pawl into the proper location with respect tothe rachet of the fullstroke compelling mechanism and then locked insuch position. The locking means may at any time be selectively unlockedto permit the pawl to be moved upon the eccentric pawl pin such that thedesired location can be reestablished despite wear and accumulatedtolerance build up in the tool through use. It is therefore an object ofthis invention to provide an improved form of tool adjustment mechanism.

It is another object of this invention to provide an improved form oftool adjustment mechanism for use with a full-stroke compellingmechanism.

It is another object of this invention to provide a tool adjustmentmechanism for use with a full-stroke compelling mechanism which can becontinually adjusted to compensate for changes in the tolerance andcooperation of the various portions of the associated tool.

It is still another object of this invention to provide a tooladjustment device for operation with a full-stroke compelling mechanismwhich can be selectively adjusted with simple, available tools.

It is yet another object of this invention to provide a tool adjustmentdevice for operation with a full-stroke compelling mechanism whichcomprises a pawl, selectively lockable upon an eccentric pawl pin whichcan be selectively rotated in order to position the pawl with respect tothe rachet of a full-stroke compelling mechanism.

Other objects and features of the invention will be pointed out in thefollowing description and claims and illustrated in the accompanyingdrawings, which disclose, by way of example, the principle of theinvention, and the best mode which has been contemplated for carrying itout.

BRIEF DESCRIPTION OF THE DRAWING In the drawings:

FIG. 1 is a vertical sectional view of the tool shown and described inthe above cited Bergan patent and which represents the prior art.

FIG. 2 is a side elevation of a modification to the dies employed withthe tool of FIG. 1.

FIG. 3 is an isometric drawing of a pawl and eccentric pawl pinconstructed in accordance with the concepts of the invention.

FIG. 4 is an isometric view, of the tool of FIG. 1, with a portion ofthe outer body removed in order to clearly show the cooperations betweenthe eccentric pawl pin, the pawl and the rachet of the full-strokecompelling mechanism.

FIG. 5 is a side elevation of the tool of FIG. 1 illustrating theposition of the adjustable mechanism prior to the beginning of theoperation stroke.

FIG. 6 is a side elevation of the tool of FIG. 5 illustrating theposition of the pawl during the operating cycle.

FIG. 7 is a side elevation of the tool of FIG. 5 showing the position ofthe pawl upon release of the fullstroke compelling mechanism.

Similar elements are given similar reference characters in each of therespective figures.

DESCRIPTION OF THE PREFERRED EMBODIMENT Turning now to FIG. 1 there isillustrated a toggle type crimping tool with a full-stroke compellingmechanism as found in the prior art. This figure is FIG. 6 of the abovecited Bergan patent which patent is incorporated herein by reference.Details of the Bergan patent which are common with the tool of theinstant invention will not be described again for the sake ofsimplicity. Pawl 39 is mounted upon pawl roll pin 40 and is biased to aninitial position by means of the spring 43 connected between pin 44 andarm 45 of the pawl 39. The position of the pawl with respect to thehandle 14 is maintained by means of the pawl spacers 41. The pawl nose42 is arranged to engage the teeth and lands of the rachet 35 and aftercompletion of a full-stroke is permitted to move into the rear clearancearea 36. The positioning of the pawl 39 with respect to the rachet 35 isdetermined by the shape of the nose 42, the overall shape of the pawl 39and the position of the pawl roll pin 40. Once these positions have beenestablished and the shape of the pawl established it is not possible toreadjust the device for wear at the various rotation points such as thefulcrum 37, the pin 13 or pin 33. It is necessary, due to wear at thesepoints or at the dies 17 and 18, that the shape of the pawl 39 bealtered by grinding or by providing a new pawl 39 which will permit thedesired method of operation.

Turning now to FIG. 2 the opposite side of the tool of FIG. 1 is shown.This figure illustrates a modification made to the die set which permitsgauging of the dies as will be described below. Replaceable die element17 has been replaced by another die element 17' having an extendedshoulder 50. The shiftable jaw 18 has been replaced by a furthershiftable jaw 18' which a so has an extended shoulder 52. -In theposition shown in FIG. 2, extended shoulder 50 of the replaceable dieelement 17' and the extended shoulder 52 of the shiftable jaw 18 are inengagement with one another in what is called the gauging position. Thisposition is one in which go-no go gauges may be inserted between theindenters 30 and the nets 29 of the replaceable die element 17' in orderto determine the proper crimping clearances therebetween. This will bedescribed below with reference to FIG. 4. The gauging position is theposition of maximum engagement of the replaceable die element 17 and theshiftable jaw 18' at which point the adjustable pawl arrangement to bedescribed below is in engagement with a preselected portion of therachet 35.

Turning now to FIG. 3 there is shown a pawl and an eccentric pawl pinconstructed in accordance with the concepts of the invention. Pawl 60has a nose 61, a straight face 62, an inclined face 64, a plane face 66approximately parallel with face 62 and a further inclined face 68. Inthe face 66 is placed a tapped hole 70 for the reception of a set-screw72 or the like. At the approximate jointure of the faces 62 and 64, thebody of the pawl 60 has a decreased thickness area 74 with an aperture76 placed therein. In the body of the pawl 60 is the eccentric pawl pinreceiving aperture 78. The spring 43, as shown in FIG. 1, will beattached through the hole 76 for positioning the pawl 60 with respect tothe ratchet 35. The hole 78 will be used to receive the eccentric pawlpin therethrough to couple the eccentric pawl pin with pawl 60 inrotatable relationship with respect to the rachet 35.

The pawl pin 80 has a first bearing section 82 rotatably positionedwithin a portion of the body of the tool 10 (not shown). A furtherbearing section 84 is provided for rotatably mounting within the body ofthe tool 10 (not shown). A C-ring or similar fastening device (notshown) will be positioned in the slot 86 once the eccentric pawl pin hasbeen positioned within the tool 10 to prevent the eccentric pawl pin 80from being removed from the tool body accidentally. Bearing sections 82and 84 are positioned along the same center line. An eccentric section88 is coupled between and to the bearing sections 82 and 84. Its centerline is different than that of the center line of bearing sections 82and 84 thus giving rise to the eccentricity. Slot 90 is provided in theface of the bearing section 82 to permit rotation of the eccentric pawlpin 80 with respect to the body of the tool 10. The pawl 60 will bepositioned upon the eccentric section 88 of the eccentric pawl pin 80when installed in the tool 10 and the pawl 60 will be locked to theeccentric pawl pin 80 by means of a fastener 72. In this manner,relative rotation between the eccentric pawl pin 80 and the pawl 60 isnot possible. However, pawl 60 will be permitted to rotate withrotations of the eccentric pawl pin 80.

Turning now to FIG. 4 there is shown a fragmentary portion of the tool10 illustrating the positioning and operation of the pawl 60 withrespect to the rachet 35. With the replaceable die element 17 and theshiftable jaw 18 in their gauging position, that is with the shoulderextensions 50 and 52 respectively in contact with one another, the nose61 of the pawl 60 will contact the land between the two final teeth 35aand 35b of the rachet 35. The application of a slight, further squeezingpressure to the legs 14 and 15 (not shown) of the tool 10 will cause thepawl 60 to go beyond the tooth 35]; thus releasing the pawl 60 and thefull-stroke compelling mechanism. It is essential that the nose 61 ofthe pawl 60 be in the position noted between the teeth 35a and 35b forthe proper operation of the device. In order that the replaceable dieelement 17 and the shiftable jaw 18 be properly positioned at thegauging position, to permit the insertion of gauges to determine theclearances between the indentors 30 and the nests 29 the tool must belocked at this point. If the nose 61 of the pawl 60 is not in thedesired position too much attentional pressure would be required tocause the pawl 61 to go beyond the tooth 35b into the rear clearancearea 36 of the rachet 35. Such additional force could not be applied dueto the butting of shoulder extensions 50 and 52. Therefore, it would notbe possible to bring the tool to the gauging position and then torelease it. Further, if the nose 61 of the pawl 60 was beyond the tooth35b in the rear clearance area 36 it would not be possible to lock thetool in a gauging p0- sition thus to determine the desired spacing.Although the nose 61 of the pawl 60 could initially be set in thedesired position as is done with the tool of the prior art wear at thevarious crucial points such as 33 and 13 and that the pin itself uponwhich the pawl 60 is mounted as well as wear at various other pivotalpoints in the device and at the extended shoulder dies could cause thisinitial set position to be in error. According to the instant invention,with the dies set in the gauging position the pawl nose 61 of the pawl60 can be positioned to the desired location between the teeth 35a and35b of the rachet 35 simply by loosening the fastener 72 rotating theeccentric pawl pin 80 by means of a screw driver or other similar deviceinserted into the slot 90 of the eccentric pawl pin 80. After theeccentric pawl pin 80 has been rotated to the desired position,positioning the nose '61 of the pawl 60 at the desired location thefastener 72 may be tightened to prevent relative movement between thepawl 60 and the eccentric pawl pin 80. In FIG. 5 the location of thepawl 60 prior to the start of the compression operating cycle is shown.The handles 14 and 15 are separated causing the separation of thereplaceable die element 17 and the shiftable jaw 18'. At this point acrimpable connector and a conductor to which the connector is to beassembled may be placed in the nest 29 of the replaceable die element17.

The nose 61 of the pawl 60 is now to the extreme left of the ratchet 35and fails to engage any of the teeth thereof. As pressure is applied tothe handles 15 and 14 the rachet 35 begins to sweep over the nose 61 ofthe pawl 60 from the initial position established by the spring 43. Themovement of the upper handle 15 towards the lower handle 14 causes therachet 35 to travel in a direction generally shown by the arrow in FIG.6. In the squeeze operation the nose 61 of the pawl 60 will be moved outof position causing it to engage the teeth of the rachet 35. Any releaseof the pressure applied to the handles 14 and 15 will cause the nose 61of the pawl 60 to immediately engage a tooth of the rachet 35 andprevent the tool from opening as is shown in FIG. 6. In this manner,once the pawl 60 has engaged the rachet 35 it is necessary that thecomplete compression cycle be run through to insure that a good crimp isproduced etween the connector and the conductor before release of thetool. Continued compression of the handles 14 and 15 will cause thereplaceable die element 17' and the shiftable jaw 18' to move towardsone another until they reach the gauging position, as shown in FIG. 4,at which time the nose 61 of the pawl 60 will be between teeth 35a and35b of the rachet 35. A slight additional pressure, applied to thehandles 14 and 15, will permit some flexing of the end of the member 11to permit the rachet 35 to be advanced so that the pawl 60 can move pastthe tooth 35b and into the rear clearance 36 as shown in FIG. 7. At thispoint the full-stroke compelling mechanism is cleared and the devicetool may be opened at will.

As was noted above limited flexing of the end 16 is permissable and ispossible with the device. However, the amount of flexure is limited andthus the gross mispositioning of the nose 61 of the pawl 60 could not beaccommodated by the flexure of the end 16 and thus the tools full-strokecompelling mechanism would not be released. Further, a mispositioning inthe other direction, that is past tooth 35b towards the rear clearance36 causes the tool 10 to be opened too quickly and thus would not lockat the gauging position as is desired.

With the adjustable mechanism described herein it is possible to changethe location of the pawl with respect to the rachet teeth to accommodatechanges due to wear in the extended shoulders of the dies or wear in thevarious pivotal points of the tool. Further, it is also possible now toaccommodate changes in the replaceable die element and still have thedesired full-stroke compelling mechanism operate.

While there have been shown and described and pointed out thefundamental novel features of the invention as applied to the preferredembodiment it will be understood that various omissions andsubstitutions and changes of the form and details of the deviceillustrated and in its operation may be made by those skilled inthe'a-rt, without departing from the spirit of the invention.

The embodiment of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. In a crimping tool of the toggle-type having a full-stroke compellingrachet mechanism, the improvement comprising an adjustable pawlarrangement comprising: a pawl; an eccentric pin coupling said pawl tothe body of said tool adjacent the full-stroke compelling rachet; springmeans coupled between the body of said tool and said pawl to bias saidpawl to an initial position; and locking means coupling said pawl tosaid eccentric pin to prevent relative movement between said pawl andsaid eccentric pin; said locking means permitting the locking of saidpawl to said eccentric pin after said pawl has been positioned adjacenta desired portion of said rachet.

2. An adjustable pawl arrangement as defined in claim 1, furtherincluding adjustment means coupled to said eccentric pin for rotatablypositioning said eccentric pin with respect to said rachet.

3. An adjustable pawl arrangement as defined in claim 1, wherein saideccentric pin comprises: a first bearing section arranged to berotatably mounted in a first aperture of said tool body; a secondbearing section ar ranged to be rotatably mounted in a second apertureof said tool body; said first and second bearing sections having acommon center line; and an eccentric section coupled between and to saidfirst and second bearing sections; said eccentric section having acenter line different than that of said first and second bearingsections.

4. An adjustable pawl arrangement as defined in claim 3, wherein saideccentric means further includes adjustment means for rotatablypositioning said eccentric pin with respect to said rachet.

5. An adjustable pawl arrangement as defined in claim 1, wherein saidlocking means is a screw member which can be selectively operated tocouple or uncouple said pawl to said eccentric pin, whereby said pawlcan be repositioned adjacent said rachet as required.

6. An adjustable pawl arrangement, as defined in claim 3, furtherincluding retaining means coupled to said eccentric pin, for retainingsaid eccentric pin, in said tool body while permitting rotation of saideccentric pin.

References Cited UNITED STATES PATENTS 104,426 6/1870 Clark 81-406556,394 8/1900 Deiters 81406 2,696,747 12/1954 Bergan 72410 2,738,6933/1956 Logan 72-410 2,933,000 4/1960 Wood 72410 3,406,558 10/1968Tillmann 72-416 CHARLES W. LANHAM, Primary Examiner G. P. CROSBY,Assistant Examiner US. Cl. X.R.

53 5 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION atent3,514,990 Dated June 2, 1970 Paul D. Bauknicrht and Robert Lahrheimidentified patent shown below:

Inventor(a) It is certified that error appears in the aboveand that saidLetters Patent are hereby corrected as Column 4, line 40, delete"attentional" and insert additional sen-m EAL) Attest:

mm 1:. w 1 R- EdMM-mm'h Commissioner of Patents Atteudngoffioer

